/*

 * Copyright (c) 2019, SAP SE. All rights reserved.

 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "memory/metaspace/chunkHeaderPool.hpp"

#include "runtime/os.hpp"

#include "utilities/debug.hpp"

#include "utilities/globalDefinitions.hpp"

namespace metaspace {

// Returns reference to the one global chunk header pool.

ChunkHeaderPool ChunkHeaderPool::_chunkHeaderPool(false);

ChunkHeaderPool::ChunkHeaderPool(bool delete_on_destruction)

  : _num_slabs(), _first_slab(NULL), _current_slab(NULL), _delete_on_destruction(delete_on_destruction)

{

}

ChunkHeaderPool::~ChunkHeaderPool() {

  if (_delete_on_destruction) {

    // This is only done when tests are running, but not for the global chunk pool,

    // since that is supposed to live until the process ends.

    slab_t* s = _first_slab;

    while (s != NULL) {

      slab_t* next_slab = s->next;

      os::free(s);

      s = next_slab;

    }

  }

}

void ChunkHeaderPool::allocate_new_slab() {

  slab_t* slab = (slab_t*)os::malloc(sizeof(slab_t), mtInternal);

  memset(slab, 0, sizeof(slab_t));

  if (_current_slab != NULL) {

    _current_slab->next = slab;

  }

  _current_slab = slab;

  if (_first_slab == NULL) {

    _first_slab = slab;

  }

  _num_slabs.increment();

}

// Returns size of memory used.

size_t ChunkHeaderPool::memory_footprint_words() const {

  return (_num_slabs.get() * sizeof(slab_t)) / BytesPerWord;

}

#ifdef ASSERT

void ChunkHeaderPool::verify(bool slow) const {

  const slab_t* s = _first_slab;

  int num = 0;

  while (s != NULL) {

    assert(s->top >= 0 && s->top <= slab_capacity,

           "invalid slab at " PTR_FORMAT ", top: %d, slab cap: %d",

           p2i(s), s->top, slab_capacity );

    s = s->next;

    num ++;

  }

  _num_slabs.check(num);

}

#endif

} // namespace metaspace